1. Cricoid Pressure: Are We Really Doing it Right?
Nichole M. Doyle, MD
University of Kansas SOM Wichita
4/14/2011

2. Outline Introduction Cricoid Pressure Study Cricoid Pressure Basics
Cricoid vs BURP procedure

3. Cricoid Study Design
143 Anesthesiolgists, Residents,CRNA’s, OR Staff and RT’s
Pre-didactic questionairre
Simulated RSI/Emergent intubation
Short power point presentation
Allowed to practice on simulator
Returned 2 months later for repeat testing

4. Questionnaire Yrs of experience Formal training
How cricoid pressure was learned
Indications and Contraindications for CP
When is CP released
How many Newtons should be applied
What is a Newton
Did person feel adequately trained

5. Results From Questionnaire
100% found the didactic training beneficial
99% of participants found the simulation beneficial
55% of participants learned to apply cricoid pressure from observation or OJT
72% had not received formal training
Also say
Prior to training 100% of participants decreased the amount of cricoid pressure applied during direct laryngoscopy, but after training, this decreased to 22%. However this was an incidental finding from our study

6. Results from Questionnaire Cont.
20% incorrectly believed primary function was to improve visualization
7% Knew the proper amount of pressure to apply
11% Knew what a Newton was
67% Felt inadequately trained

7. Results From Simulation
Correct Location Improved from 45%-88%
Correct amount of pressure before LOC improved from 68%-74%
Correct amount of pressure after LOC improved from 3%-56%
Drop in Pressure during DL decreased from 100% to 29%
Cricoid pressure released appropriately increased from 94%-98%
Location MD p<.001; CRNA p=.004; OR Pp<.001; Pressure MD p=.05;

8. Cricoid Pressure
Pressure applied to cricoid cartilage with goal of occluding hypopharynx and prevent aspiration
Still controversial but still a medicolegal standard of care
Cricoid cartilage is used because it’s the only complete ring
Often confused with BURP procedure

9. Technique
Using the thumb and index finger on either side of the cricoid cartilage apply 10 Newtons of pressure directly backwards prior to induction of anesthesia
Increase pressure to 30 Newtons upon loss of consciousness
Maintain pressure until position of endotracheal tube is confirmed by breath sounds and permission is given by intubating personnel
10 Newtons is the force of gravity on an object with a mass of approx 1kg
Therefore approx 2-3lbs for awake pts and approx 7lbs-10lbs for unconscious pts

10. Anatomy

11. Demonstration of application

12. Indications Code/Emergent Intubation Full Stomach/Recent Meal
Delayed gastric emptying
Trauma, acute abdomen
Incompetent lower esophageal sphincter
Hiatal hernia, pregnancy, severe symptomatic GERD

13. Contraindications Suspected cricotracheal injury Active vomiting
Unstable cervical spine injuries
Foreign body in upper airway
Tracheotomy

14. Complications Cricoid Pressure may…. Interfere with ventilation
Make passage of ETT difficult
Alter laryngeal visualization
Esp at pressures > 40 N
In awake pts has promoted vomiting
Esophageal rupture
Decreased lower esophageal sphincter tone
Cricoid Cartilage fracture

15. BURP Procedure BURP (Backward, upward, rightward, procedure)
Is done with the objective of improving view of intubator during direct laryngoscopy
Pressure applied to thyroid cartilage
Much less pressure than what is applied during application of cricoid pressure

16. Final Points Pressure amounts given are for adults
Release cricoid pressure if it interferes with ventilation or visualization
Maintain constant pressure after LOC occurs until ETT position confirmed
BURP and cricoid pressure are different maneuvers with different goals
Training improves location and amount of pressure applied
Participants felt more comfortable applying CP after teaching
As a whole Location 38%-54%; Proper pressure 3%-54%;

17. THANK YOU Questions? References
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Ashurst N, Rout CC, Rocke DA, Gouws E. Use of mechanical simulator for training in applying cricoid pressure. Br J Anaesth 1996 Oct;77(4):
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Rice MJ, Mancuso AA, Gibbs D, Morey TE, Gravenstein N, Deitte LA. Cricoid Pressure Results in Compression of the Postcricoid Hypopharynx: The Esophageal Position is Irrelevant. International Anesthesia Research Society 2009;109:
Matthews, GA. Survey of cricoid pressure application by anaesthetists, operating department practitioners, intensive care and accident and emergency nurses. Anaesthesia 2001;56:
Marcus, Adam. Legal, Clinical Data Paint Conflicting Picture of Cricoid Pressure. Anesthesiology News 2010;36.